Turns out that the storage battery discharged, even though the battery disconnect switch was "in use" position (which is supposed to keep the storage battery charged) and the Interstate had land power to it. When the battery was discharged almost all 12V
items stopped: the LP gas detector, DVD, propane on/off, generator starter etc. Strangest thing was the monitor panel showed the battery charged - so I never thought twice about it.
I notified Airstream this issue should be stated on their operating manual.